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Date: Wed, 2 Mar 2011 08:19:18 -0800
Message-ID: <AANLkTin80NPz77FAouV5=-5MQu8cYCF6MVxc7HXr=wpw@mail.gmail.com>
Subject: Re: Question about Clustered Setup in two data centers
From: Mahadev Konar <mahadev@apache.org>
To: user@zookeeper.apache.org
Cc: Zsolt Beothy-Elo <zbeothy-elo@talend.com>
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Hi Zsolt,
  Sorry to disappoint but there isnt any way of running zookeeper on 2
machines and calling it reliable. You can run a set of 2 machines for
a quorum of 3 but if one of the machine goes down then zookeeper goes
down. Also, a data center of 2 has issues since which ever datacenter
you place the max part of the quorum in, in case of death will caiuse
the ZK cluster to fail.  I am assuming you are talking about ZK cross
data center.

thanks
mahadev

On Wed, Mar 2, 2011 at 6:57 AM, Zsolt Beothy-Elo <zbeothy-elo@talend.com> w=
rote:
> Hi all,
> in our product we currently implement to use ZooKeeper in conjunction wit=
h CXF to dynamically manage available services and endpoints. Unfortunately=
 one of our customers is not very happy of having to run a minimum of three=
 ZooKeeper server instances to ensure fail over. The customer has two data =
centers in different locations where data and applications are replicated a=
nd some big-ip appliance in front of the data centers. If one data center f=
ails everything must still be operable. So he would prefer to only have two=
 =A0instances one in each data center. I would be grateful for some advise =
how to best cope with these contradicting requirements.
>
> Cheers,
> Zsolt Beothy-Elo